Methodological Challenges of a Megadiverse Ecosystem

‘Megadiversity’ originated as a term in the context of biodiversity conservation in the late 1980s (Mittermeier et al. 2004). It refers to countries with an extremely high level of species richness, usually found in the tropical realm, one or two orders higher in magnitude than in most temperate zone countries. In many ways countries or areas of megadiversity coincide with the slightly longer-established concept of biodiversity hotspots (Myers et al. 2000; Brummitt and Lughadha 2003; see Chapter 2 in this volume). Unlike the concept of hotspots, megadiversity also attempts to take into account degrees of endemism, phylogenetic relatedness, and other measures of diversity applied for identifying biodiversity hotspots as opposed to pure numbers of species or taxa per unit area. More than any academic differentiation, however, the term megadiversity was recently taken up and promoted at the political level, particularly under the Convention of Biological Diversity (CBD), as well as the Convention on International Trade in Endangered Species of Fauna and Flora (CITES). Following the original meeting in Cancun, Mexico, in February 2002, 15 countries formed a group of ‘Like-Minded Megadiverse Countries’ (LMMC) as a forum to address the specific challenges for biodiversity conservation and sustainable use faced by countries with disproportional high levels of biodiversity (‘Cancun declaration 2002’). Later joined by Australia and the USA, this informal group of countries comprises many but by no means all of the recognized global biodiversity hotspots.